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Abstract: Crystalline silicon thin film solar cells, based on the epitaxial wafer equivalent, require a reflecting interlayer between substrate and active layers to increase the generated current and reach similar efficiencies as wafer based solar cells. With the epitaxial lateral overgrowth technique, a reflecting dielectric layer can be implemented. In this paper results of solar cells with overgrown, patterned SiO2 films are shown. A beneficial optical effect due to the interlayer and also a reduced effective diffusion length within the epitaxially grown silicon layer are observed. Cells with reflecting interlayer and non-optimized absorber layer thicknesses therefore exhibit lower efficiencies than cells without SiO2. Slightly higher currents are observed with textured front sides. Significantly increased effective diffusion lengths and cell performances can be reached with non-merged active silicon layers. Reasons might be the avoidance of defects generated at merging points and of unpassivated surface areas in voids remaining where two growth fronts merge. [Copyright &y& Elsevier]

Cellular processes are remarkably effective across diverse temperature ranges, even with highly conserved proteins. In the context of the microtubule cytoskeleton, which is critically involved in a wide range of cellular activities, this is particularly striking, as tubulin is one of the most conserved proteins while microtubule dynamic instability is highly temperature sensitive. Here, we leverage the diversity of natural tubulin variants from three closely related frog species that live at different temperatures. We determine the microtubule structure across all three species at between 3.0 and 3.6 Å resolution by cryo-electron microscopy and find small differences at the β-tubulin lateral interactions. Using in vitro reconstitution assays and quantitative biochemistry, we show that tubulin's free energy scales inversely with temperature. The observed weakening of lateral contacts and the low apparent activation energy for tubulin incorporation provide an explanation for the overall stability and higher growth rates of microtubules in cold-adapted frog species. This study thus broadens our conceptual framework for understanding microtubule dynamics and provides insights into how conserved cellular processes are tailored to different ecological niches., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Eukaryotic cells typically express multiple tubulin isoforms that form the microtubule cytoskeleton. A new study of the evolution and functional diversification of pools of tubulin isoforms suggests that these proteins are part of a co-evolving network that includes the extensive microtubule interactome., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Geriatric depression is challenging to treat owing to age-related changes in pharmacokinetics and comorbidities. Although renal insufficiency and multimorbidity are typical geriatric complications that cannot be completely separated from each other, no study has examined the influence of these factors on the serum concentrations of antidepressants. For the first time, we evaluated the effects of these factors in combination on the dose-corrected serum concentration (C/D) of antidepressants in geriatric patients., Methods: In this retrospective study, data from 123 geriatric patients in a gerontopsychiatric day care unit at the University Hospital of Würzburg were analyzed. Multiple linear regression analysis and analysis of variance with confounders were used to examine the associations between glomerular filtration rate (GFR) and stages of renal impairment and the C/D of venlafaxine, mirtazapine, sertraline, and escitalopram corrected for multimorbidity, sex, lithium intake, and the number of triple whammy drugs., Results: GFR (P < 0.001, ß = -0.070) was associated with the C/D of the active moiety of venlafaxine (N = 32). GFR, multimorbidity, and sex were not associated with the C/D of mirtazapine, escitalopram, or sertraline., Conclusions: As the influence of sex may be less pronounced than that of decreasing GFR in terms of the C/D of the active moiety of venlafaxine in geriatric patients, we recommend considering the GFR for dose adjustment rather than sex. In conclusion, even in patients with mild renal impairment, serum venlafaxine concentration should be monitored to prevent overdosing. Mirtazapine, sertraline, and escitalopram may be well-suited antidepressants for geriatric patients with renal function impairment stage 2-3 as well as multimorbidity., Competing Interests: M. Scherf-Clavel received an advisor honorarium from Rovi. The remaining authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Cytoskeletal dynamics are essential for cellular homeostasis and development for both metazoans and protozoans. The function of cytoskeletal elements in protozoans can diverge from that of metazoan cells, with microtubules being more stable and actin filaments being more dynamic. This is particularly striking in protozoan parasites that evolved to enter metazoan cells. Here, we review recent progress towards understanding cytoskeletal dynamics in protozoan parasites, with a focus on divergent properties compared to classic model organisms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this study., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The shells of the Pinnidae family are based on a double layer of single-crystal-like calcitic prisms and inner aragonitic nacre, a structure known for its outstanding mechanical performance. However, on the posterior side, shells are missing the nacreous layer, which raises the question of whether there can be any functional role in giving up this mechanical performance. Here, it is demonstrated that the prismatic part of the Pinna nobilis shell exhibits unusual optical properties, whereby each prism acts as an individual optical fiber guiding the ambient light to the inner shell cavity by total internal reflection. This pixelated light channeling enhances both spatial resolution and contrast while reducing angular blurring, an apt combination for acute tracking of a moving object. These findings offer insights into the evolutionary aspects of light-sensing and imaging and demonstrate how an architectured optical system for efficient light-tracking can be based on birefringent ceramics., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Herein we report the structure-activity relationship (SAR) studies and optimization of new highly potent and selective CRTH2 receptor antagonists as potential follow-ups of our previous reported clinical candidate setipiprant (ACT-129968) for the treatment of respiratory diseases. Structural modification of the amide part of setipiprant (ACT-129968) led to the identification of the tetrahydrocarbazole derivative (S)-B-1 (ACT-453859) ((S)-2-(3-((5-chloropyrimidin-2-yl)(methyl)amino)-6-fluoro-1,2,3,4-tetrahydro-9H-carbazol-9-yl)acetic acid). This compound which displayed a substantial improvement in potency in the presence of plasma versus setipiprant (ACT-129968) has exhibited an excellent overall pharmacokinetic profile. Further lead optimization to overcome a safety issue as observed in non-clinical studies with (S)-B-1 (ACT-453859), led to the discovery of the 4-azaindole derivative (S)-72 (ACT-774312) ((S)-2-(8-((5-chloropyrimidin-2-yl)(methyl)amino)-2-fluoro-6,7,8,9-tetrahydro-5H-pyrido[3,2-b]indol-5-yl)acetic acid) which was selected as a potential follow-up of setipiprant (ACT-129968)., (© 2023 Wiley-VCH GmbH.)

Nup98 FG repeat domains comprise hydrophobic FG motifs linked through uncharged spacers. FG motifs capture nuclear transport receptors (NTRs) during nuclear pore complex (NPC) passage, confer inter-repeat cohesion, and condense the domains into a selective phase with NPC-typical barrier properties. We show that shortening inter-FG spacers enhances cohesion, increases phase density, and tightens such barrier - all consistent with a sieve-like phase. Phase separation tolerates mutating the Nup98-typical GLFG motifs, provided domain-hydrophobicity remains preserved. NTR-entry, however, is sensitive to (certain) deviations from canonical FG motifs, suggesting co-evolutionary adaptation. Unexpectedly, we observed that arginines promote FG-phase-entry apparently also by hydrophobic interactions/ hydrogen-bonding and not just through cation-π interactions. Although incompatible with NTR·cargo complexes, a YG phase displays remarkable transport selectivity, particularly for engineered GFP NTR -variants. GLFG to FSFG mutations make the FG phase hypercohesive, precluding NTR-entry. Extending spacers relaxes this hypercohesion. Thus, antagonism between cohesion and NTR·FG interactions is key to transport selectivity., (© 2023. The Author(s).)

In an active, crowded cytoplasm, eukaryotic cells construct metaphase spindles from conserved building blocks to segregate chromosomes. Yet, spindles execute their function in a stunning variety of cell shapes and sizes across orders of magnitude. Thus, the current challenge is to understand how unique mesoscale spindle characteristics emerge from the interaction of molecular collectives. Key components of these collectives are tubulin dimers, which polymerise into microtubules. Despite all conservation, tubulin is a genetically and biochemically complex protein family, and we only begin to uncover how tubulin diversity affects microtubule dynamics and thus spindle assembly. Moreover, it is increasingly appreciated that spindles are dynamically intertwined with the cytoplasm that itself exhibits cell-type specific emergent properties with yet mostly unexplored consequences for spindle construction. Therefore, on our way toward a quantitative picture of spindle function, we need to understand molecular behaviour of the building blocks and connect it to the entire cellular context., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)